TSI Blood Test - More Information

Thyroid-stimulating immunoglobulins (TSIs) are autoantibodies that contribute to thyroid dysfunction. Specifically, TSIs can cause overactive thyroid activity by activating receptors that are typically turned on by thyroid-stimulating hormone, or TSH, which is why the TSI blood test is sometimes done with the TSH test. Elevated TSI blood levels are also seen in Graves' disease, Hashimoto's thyroiditis, thyrotoxicosis and other autoimmune conditions.

To get a TSI lab test near you, just order online and get your blood drawn at your selected Quest lab. For an example of what your TSI lab results will look like, please click on the TSI sample report link above.